Sewing machine



Spt. 9, 1952 N. v. CHRISTENSEN SEWING MACHINE Filed Sept. 7, 1946 ll Sheets-Sheet l HIIIIIII IIIIIIIIII INVENTOR. NQRMAN .V. CHR\5TEN5EN1 ATTOENE Sept. 9, '1952 N. v. CHRISTENSEN SEWING MACHINE ll Sheets-Sheet 2 Filed Sept. 7, 1946 INVENTOR.

NORMAN.V.CHR|5TEN5EN ATTORNEY Sept. 9, 1952 N. v. CHRISTENSEN SEWING MACHINE ll Sheets-Sheet 3 Filed Sept. 7. 1946 IN VEN TOR.

NORMANMCHNSTENSEN p 1952 N. v. CHRISTENSEN 2,609,770

SEWING MACHINE Filed Sept. '7, 1946 ll Sheets-Sheet 4 uui'lil'i'iiuuluml'niiii' .*.*.'.I mun: l llllllllllu. a q lllElllH U 9%: 5!: llllll 8 ET 21 f E a wa 1% 8 g g M II :2 m 8 f Q Q I INVEN TOR.

NORMANM CHRISTENSEN BY ATTORNEY Sept. 9, 1952 N. v. CHRISTENSEN SEWING MACHINE 11 Sheet s-Sheet 5 Filed Sept. 7, 1946 INVENTOR. BY NORMANVCHRISTENSEN ATTOR/SIE';

Sept. 9, 1952 N. v. CHRISTENSEN 2,609,770

SEWING MACHINE Filed Sept. 7, 1946 ll Sheets-Sheet 7 F IGJO.

INVENTO'R.

NORMAN.V.CHR\5TENSEN AZJWEYE Sept. 9, 1952 N. v. CHRISTENSEN SEWING MACHINE 11 Sheets-Sheet 8 Filed Sept. '7, 1946 INVEN TOR.

NORMAN .V. CHR\STENSEN N. V. CHRISTENSEN SEWING MACHINE Sept. 9, 1952 11 Sheets-Sheet 9 Filed Sept. '7, 1946 a iliL.

FIG. I5. 1

FIG. I6.

20 l f F'IGJ? INVENTOR.

' NORMAN .v CHR\STENSEN ATTORZYE'Y' Sept. 9, 1952 N. v. CHRISTENSEN 2,609,770

SEWING MACHINE Filed Sept. 7, 1946 ll Sheets-Sheet .10

FIG. 18.

FIG. I9.

INVENTOR.

NORMAN .v. CHRISTENSEN AZTORNE'Y N. v. CHRISTENSEN 2,609,770

SEWING MACHINE 11 Sheets-Sheet ll ZNVENTOR.

NORMAN.V.CHRI5TENSEN ATTORNEY Sept. 9, 1952 Filed Sept. 7, 1946 Patented Sept. 9, 1952 SEWING MACHINE- Norman V. Christensen, Chicago, Ill., assignor to Union Special Machine Company, Chicago, 11]., a corporation of Illinois Application September 7, 1946, Serial No. 695,426

7 Claims. 1

This invention relates to sewing machines and more particularly to machines of the lock stitch and double locked stitch types.

An object of the invention has been to provide for the economical and emcient production on a large scale of sewing machines of the types indicated.

avertical axis rotary hook, lockstitch machine or a vertical axis oscillatory looper, double locked stitch machine.

A still further object of the invention has been to providefor such interchangeable use of rotary hooks and oscillatory loopers in either a needle feed machine or a plain feed machine, 1. e., one not provided with needle feed.

In attaining the foregoing objects a number of important, special features have been developed. Of primary importance is the development of a self-contained oscillating looper saddle unit which may be used interchangeably with a vertical hook saddle unit. Thearrangement is such that a 1 to 1 driving ratio may be provided between the main rotary shaft in the base i of the machine and a shaft within the looper saddle While, a l to 2 ratio may be provided between said main shaft and the hook carrying shaft of the vertical hook saddle. A sewing machine which is otherwisecomplete, with or without a needle feed action, may be formed either into a double locked stitch machine by the use of the looper saddle or into a locked stitch machine by the use of the hook saddle. Other minor changes in, the machine assembly may be desirable in converting from one type to the other, but thesechanges are of a character well within the experience of an operator or mill mechanic. They include changes in the typeor spacing of the needles, the throat plate, presser foot, thread 'takeup eyelets, feed dog,

, and the like.

Another special feature, the provision of an improved vertical rotary hook unit, This is of simple, compact constructionand embodies an improved, highlygeffective lubrication system.

A further feature is the provision of a simple but effective puller mechanism which cooperates ywith the regular work feeding mechanism to insure the proper and uniform advance of the work. This puller mechanism is of such character that it may readily be applied to or omitted from the machine, depending upon the particular requirements of the machine.

Still another feature of the invention is the provision of either a two-motion or a four-motion looper, as desired, in the vertical axis looper saddle to be embodied in the machine. Both types of loopers are of simple construction and adapted for reliable operation in conjunction with the needle. Moreover, the arrangements are such that a plurality of loopers may readily be incorporated in a single unit for cooperation with a plurality of needles. A single looper may, if desired, cooperate with a plurality of needles. The four-motion loopers are driven by a single driving member which im-parts the four motions.

The provision of a self-contained lubrication system in each of theloopersaddle units is a still further feature of the invention.

Also, the adaptation of the machine for either a rotary takeup, of improved construction, or an oscillatory or reciprocatory takeup, as desired, is still another feature of the invention.

Improved presser means are also provided in conjunction with the work feeding devices. The arrangement is suchthat separate presser means are provided for theregular; four-motion feed dog and an auxiliary puller roller and means operable at will are provided for disabling both of these presser means simultaneously or for disabling one alone.

Other objects, features, and advantages will appear from a detailed description of certain illustrative embodiments of the invention which will now be given in conjunction with the accompanying drawings, in which:

Fig. 1 is a full-sized, top plan view ofa part of the work supporting portion of a machine embodying features of the invention, certain cover plates being removed from the work supporting surface to expose the parts beneath;

Fig. 2 is a longitudinal vertical section through the major portion of the illustrative machine on a reduced scale, the remainder being shown in front elevation;

Fig. 3 is a view, partly in end elevation and partly in vertical section, .taken substantially along the1ine;3 -3, of Fig-2;.

Fig. 4 is a' bbtt-omplan view of the machine with atcov'er plate removed to expose the interior mechanisrm: l

Fig; is a fragmentaryjview; partly in bottom plan and partly in horizontal section taken intermediate the top and bottom of the base portion of the machine;

Fig. 6 is a transverse vertical section through the machine taken substantially along the line 66 of Fig.2;

Fig. 7 is a detail view in vertical section through the work supporting portion of the machine, taken substantially along the line 3-3 of Fig. 2, and illustrates a modified form of work feeding mechanism from that shown in Fig. 3;

Fig. 8 is a vertical section through the work supporting portion of the machine taken along the line B--8 of Fig. 1;

Fig. 9 is a Vertical section through a looper saddle unit embodied in the machine and is taken along the line 9-9 of Fig. 1;

Fig. 101is a schematic view showing in plan a looper carrier provided with a plurality of loopers and operating linkage therefor adapted to impart a four-motion movement thereto;

Fig. 11 is a similar schematic view showing a looper carrier having a single looper mounted thereon, the path of the end of the looper and of other points of the system bein indicated;

Fig. 12 is a, view in transverse vertical section through the Work'support, similar to Fig. 8, but showing a modified form of looper which has only a two-motion movement; 7 H

Fig. 13 is a vertical sectional view taken along the line l3l3 of Fig. 12;

Fig. 14; is a view similar to Fig. 11 in relation to the two-motion looper of Fig. 12 and shows the-path of the two-motion looper;

Fig. 15 is a fragmentary view, in top plan, of the work support of the machine equipped with vertical axis hooks in lieu of the loopers of Fig. 1;

Fig. 16 is a transverse vertical sectional view,

similar to Fig. '8, illustrating thervertical axis hook and is .taken along the line l6-|-6 of Fig. 15;

Fig. 17 is a fragmentary detail view, in section along the line.l1 l'l of Fig. 16, showing a portion of the hook saddle construction;

Fig. 18 is a fragmentary bottom plan view of a portion of the base of the machine embodying the vertical axis'hook saddle, a bottom coverplate being removed therefrom;

Fig. 19 is a vertical sectional view through the hook saddle unit, taken along the line [9-19 of Fig. 15;

Fig. 20 is a vertical sectional view through the hook saddle of Fig. 16 and is taken along the line 20-20 of Fig. 16;

Fig. 21 is a fragmentary detail view, in horizontal section, taken along the line 2l2l of Fig. 29; and

Fig. 22 is a fragmentary detail view, in vertical section, taken along the line 22-22 of Fig. 20.

Referring now to the drawings and more particularly to Figs. 1, 2, and 3, the illustrative machine is of the fiat bed type embodying a frame having a work supporting portion or base 10, a vertical standard ll rising from one end of the base, and an overhanging arm I2 extending over the base from the upper end of the vertical standard. Within the, overhanging arm there is mounted, in suitable bearings, main shaft it and pulley M. A train of gearing l5 within the vertical standard connects thenshaft I 3 with a a collar'memberjasecured to the needle bar. At

'itsilower end the needle bar may be provided with a needle carrying frame 24, of any suitable form,

serving to support a needle or plurality of needles 25. For the purposes of illustration two needles are shown, these being relatively widely spaced.

Loop takin'g mechanism Referring now more'particularly to Figs. 1, 8. and 9, there is provided in one form of the machine, complemental' lo'opetaking means in the form of'loopers" 26 mounted .TOI oscillation "about vertical axes. Each of these loopers'isxcarried by an oscillatable carrier 2'! having ai-relat'ively large central portion provided with an'opening main shaft I 6 suitably journalled in the base portion of the frame. Gearing I 5 includes a gear secured to each ofthe shafts l3 and I6 and an adapted to receive an eccentric portion"28;of "a vertically disposed "hollow shaft "2.9. shaft is mounted for rotation in suitable bearings 39 and 3! carriedby an auxiliary frameor bracket or saddle 32 "which i 'iadjustably mounted on-the base portion of the main frame of'th'e' machine. For this purpose the "saddle is preferably provided with a forked'extension 1% adapted to surround a bearing sleeve 34 (Fig. 4') carried 'bya fixed lug 35 integral with and extending downwardly from the under surface or the wink :support. A screw 3'6: may he provided .for'drawing the forked end's 3'3 together to clamp the same in desired position'upon'the bearing'sl'eeve '34. The opposite end of the saddle preferably in the form of 'a lu'g 31 having an elongate'd'slot 38 extending therethrough 'a'nd adapted to receive a screw 39 which has thread'ed engagement with a log iii'on the-baseportioncf th'e'm'ain frame.

ii /hen thescrews -'36 and '3 9' are'loose'ned the' saddle' may be shifted axially-along th'e s'haftlli to any "desired position and'itmay then be clamped in 'set position lay-tightening "the screws 36 and 3%. Adjustment may thus "be inade for any desired needlespacing and positioning.

For the purposeof drivingthe shaft Z'Sthere is mounted onthef-shaft i-6a spiral -gear arranged to mesh with a companion 'spiralgear which is secure -to the shaft 29' by means of a set-screw fi3. Gears: is "adjustable axially along theshaft i -l3,-to 'conf orrn withthe adjustment of the saddle unitfa's' explained ab'ovega'nd is secured to the shaft for rotation "by means of a set screw, as-shotvn in Fig. 8. at its upper end the shaft 2 9 'h'a'sa crank pin extension or second eccentric 4'4,-'above the eccentric '28, which is adapted "to receive' cne end of' a link'or conn cr n ro'a 45; "opposite end or sai'dli n'k is secured by ascrew' wtoa lever upivetau supported on the saddle unit by means of a pin'48' held in place by a setscrew as. r :The outer free end of the lever 4'! is secured by means of a screw '59 to one end of a link s l, he Opposite end of which is secured by a' sjcrew52to the looper carrierfll I It will be apparentthat" due to the mounting and operating linkage described with respect to 7 the carrier 21, the latter will be rocked about the eccentric portion 28 of the shaft through the 54. These combined movements will impart to the freeend of the looper 26 the path indicated by the arrows and the crescent 55, by virtue of the bodily movement imparted to the carrier 21 by the eccentric 28 and the rocking movement imparted to this carrier by the crank pin 44 through the link 45, lever 41 and link The corresponding relative positions of the parts for each 30 of rotation of the shaft 29 are indicated by the numerals 0 to H inclusive around the several orbital paths described above. In Fig. 11 the parts are shown in the positions they assume at point Tin the cycle of rotation of shaft 29. From the pathdesignated 55 it will be seen that the looper is not only oscillated to pick up and shed one or more needle loops, but it is also given a needle avoid movement.

In Fig. there is shown'the possibility of mounting a plurality of loopers a and 26b upon the same looper carrier 21a. This carrier may be so mounted as to receive the same fourmotion movement as described in connection with Fig. 11. The arrangement may be such that each looper cooperates with a needle, 25a or 25b, the foremost and rearmost positions of which are indicated in Fig. 10 for a needle feed machine. Thus a single looper carrier may bring about the production of two lines of stitching, each involving three threads, i. e., a looper thread and two needle threads. It will be understood that each looper may cooperate with but a single needle, if desired.

,aeoawo I lock nut 65 serves to. hold thestem in any posi- Means are preferably provided for automatic lubrication of the principal wear surfaces in the looper unit. For this purpose, a lubricant reservoir 5B is provided directly in the bracket or saddle, the lubricant being introduced into this reservoir through an inlet opening at the top which is accessible through the work supporting surface upon the removal of a small plate Illa (Fig. 8). This inlet opening is then preferably closed by a Gits cup cap 51. A lucite gauge 58 is also preferably provided to indicate at all times the quantity of lubricant in the reservoir. The lubricant isdelivered from a point adjacent the bottom of the reservoir through a small sleeve 59 into the interior of which the oil passes through smallopenings 60 in the wall of the sleeve. At the inner endof the sleeve a restricted passage BI is provided for conducting the oil into a small pocket-62 formed at the base of the shaft 29.

soilthe work or the stitching thread, a needle threaded, as indicated at 64, to cooperate with threads on the interior of the sleeve 59. The end i of the. stem may be provided with a slot to receive .a screw-driver for appropriate adjustment.

tion to which it may be adjusted. v

To elevate the oil. from the. pocket 92 to the various surfaces to be lubricated, a spirally grooved core pin 69 is provided within a bore extending axially of the shaft 29. A relatively loose fit exists between the pin and the bore of the shaft. At its lower end the core pin has a flattened extension 6! cooperating with a slot or groove 68 formed in theupper surface of a bottom closure plate 69ffor the reservoir 55 and pocket 62. This bottom closure plate may be secured to the hook saddle in any suitable way, as by means of screws and it should be appropriately gasketted. It will be apparent that due to the construction described, the core pin will remain stationary While the shaft is rotated and, as a result, the oil will be drawn upwardly from the pocket 92 along the inclined or spiral groove in the core pin bya viscous pump action. At the upper end of the core pin a part of the lubricant will be discharged through a small passage 19 to the cooperating surfaces between the eccentric 28 and the cylindrical portion of the looper carrier 21. Another .part of the oil will be directed upwardly through the passage H extending axially of the crank pin 44. A laterally extending passage 12 then serves to direct this lubricant to the cooperating surfaces between the crank pin and the pitman 95. If desired, a portion of the lubricant pumped by the action of the core pin may be discharged laterally through small passages, not shown, to the cooperating surfaces between the shaft 29 and the bearing members 39 and 3|. However, other means of lubrication of these bearings may be, and preferably are, provided.

. In Figs. 12, 13, and 14, a slightly modified form of looper unit is illustrated. In this modified construction the shaft 29 is provided with an enlarged concentric portion 13, in lieu of the eccentric 25, about which a looper carrier 14 may be oscillated. This looper carrier may be provided with one or more loopers 15 attached by means of a screw I6 or the like. In other respects the construction of the modified unit may be identical with that previously described. By elimination of the eccentricity of the portion 28 of the looper operating shaft, the looper will be given a simple oscillatory movement along the path ll of Fig. 14. Because of the arcuate form of the looper l5, it has'been found that proper stitch formation may readily be achieved without the necessity of a four-motion movement of the looper. i

. Vertical hook units The machine, as hereinabove described, is capable of being readily converted from a double locked stitch machine to a regular or single lock stitch machine by the simple substitution of a different type of saddle for the looper saddle described above. Thus, referring to Figs. 15 to 22 inclusive, there may be substituted for the looper saddle a vertical axis hook unit comprising a bracket or saddle 18 having a forked extension 19 adapted to be adjustably mounted upon the bearing sleeve 34 and locked in adjusted position thereon by a screw 80. At its opposite end the saddle maybe provided with a lug 8| having an elongated slot 82 adapted to receive a screw 83 for adjustable attachment of this end of the saddle to the lug 40, of the main frame of the machine. It will be seen, in general, that the vertical hookunit may beemployed interchange- 'ably with one or another of the looperiunits by spaced projecting portions of the hook saddle.

A spiral gear 8! secured to the shaft in any suitable wayintermediate the bearings 35 and se is arranged to be driven by a spiral gear 88 secured to'the shaft I6. Gear 88 is shiftable axially along the shaft It to correspond with the adjustment ofthe hook saddle and is secured in any desired position by a set-screw. The relationship between the gears 81 and 88 is such that the hook shaft 84 will be given two revolutions for each revolution of the shaft I6. Between the upper surface of the gear 07 and the under surface of the bearing 85, a spacing and thrust bearing plate 89 is provided. Extending upwardly from the lower arm of the hook saddle adjacent the bearing 85 is a small ledge t0, as best shown in Figs. 16 and 1'7, which serves to prevent the gear 81 from falling out when the hook shaft 84 is removed for purposes of inspection or repair andwhen the machine is then tilted back on its supporting table. The rotary hook comprises a rotating component 9|, secured to the upper and the shaft 84 by means of a set-screw 92, and a stationary component 93 forming a bobbin case holder. This stationary component is provided with laterally projecting ribs 94 arranged to cooperate with a raceway'95 in the rotating component, in a manner well known in the art.

A finger 96 is provided for engagement with a projection 92% on the bobbin case holder for the purpose of shifting this holder slightly'in a counterclockwise direction (Fig. 15) at a point in the stitch forming cycle at which the needle thread loop is to be pulled away from a retainer (not shown) that normally engages the bobbin case holder to restrain it against rotation with the rotary component of the hook. The loop releasing finger 90 is adjustably carried by an arm 98 whichis forked to receive the upper end of a shaft I to which it is clamped by means of a screw 99. The shaft I00 is journalled in bearings Nil and I02 carried by the hook saddle. A screw I03 may be provided at the top of the shaft I80 to assist in looking the arm 98 in the desired position on the shaft. At its lower end the shaft IEO has secured thereto, in any suitable way, an arm I04 to which is pivotally connected, by means of a bolt I05, the outer end of a pitman I06 having a strap portion surrounding an eccentric I0! carried by the shaft 84 adjacent its lower end. The connections described are such that upon rotation of the shaft '84, the arm led and shaft I00 will be rocked at an appropriate point in the cycle to carry the finger 96 against the projection 97 for the purpose hereinabove mentioned.

Provision is made for automatic lubrication of the major wear'receiving surfaces of the hook unit. For this purpose the saddle is provided with a relatively large oil reservoir I08, .at one 7 side of th-e'fshaft 94, and a smaller reservoir IE9,

in any suitable'way, as by means of screws, and

an oil tight connection may be insured by the provision of a gasket.

Lubricant may be supplied to the reservoir I 08 through an opening in the top which is accessible through the-work supporting surface of the machine upon the removal of a small plate- I02) (Fig. 16), the inlet for this purpose being preferably closed by a spring urged cap III. The quantity of oil present in the reservoir may be indicated at all times by means of a lucite oil gauge IE2 visible upon the removal of plate I012. The lubricant is delivered from the reservoir I08 through a filter screen I I 3 secured to the bottom closure I I0 by means of a screw I I4. After passing through the filter the lubricant enters a small pocket I I5 in the closure plate and is then delivered laterally through asmall bore H6 in this plate to and through a small aperture II! in a hollow stud I I8 which extends through the bottom closure plate. Stud II8 preferably has a head or radially extending flange at its lower end which engages the underside of the closure plate and may be secured thereto by solder or the like. A sufiiciently tight fit is provided between the stud and the closure plate to prevent leakage of oil. Oil which passes through the aperture IIl into the interior f the stud rises through the latter and through a small aperture II9 adjacent the upper end of the stud into the bore of the shaft 84. This is due to the head of the oil in the reservoir I90. Stud I I8 remains stationary and is provided with a bearing fit in relation to the inner surface of the bore of the shaft 8 3. This fit is sufiiciently close to prevent the passage of any substantial amount of oil from the top of the stud downwardly along its outer surface into the reservoir I 09. Should any small quantity of oil follow this path, there is no serious objection, although preferably the lubricant retained within the reservoir I09 is of a dilferent character from that within the reservoir I08.

A needle valve I20 having an enlarged screw threadedhead I2I cooperating with threads at the lower end of the stud I I8 maybe adjusted to regulate accurately the amount of lubricant dclivered through the aperture II9 into the bore of the shaft as during the operation of themachine. A look nut I 2Ia may be provided to lock the needle valve in adjusted position. Within the bore of the shaft 84 there is carried, with a relatively loose fit, a spirally grooved core pin I22 having at its lower end a downwardly projecting tongue 923 which is slotted in line with the aperture I I9, as'best shown in Fig. 22. The tongue I23 is arranged to fit between two upwardly extending segments I24 at the upper end of the stud H8. The arrangement is such that the pin I22 is supported by the upper end of the studII8 and is prevented from rotation with the shaft 84 by the cooperation of the elements "I23 and I24. At the same time a passage is provided around these coacting parts so that the lubricant may rise in the bore of the shaft 84 and along the spiral groove of the-core pin. Upon rotation of the shaft 842 a viscous pump action is established by which the oil is lifted along the spiral groove to the top of the shaft 84 and is discharged into a small pocket I 25 within the rotary componentof the hook. From this pocket the oil is discharged by centrifugal force through a small tube I26 which conducts the oil to'the raceway 95. It will be understood that by proper adjustment of; the

needle valve I20 just the right amount of lubricant may be supplied to the raceway, sothat the hook will not overheat and yet no ,oil will be thrown during its rapid rotation.

Work feeding decices Feeding of the work across the work supporting surfaces in the formation of seams may be accomplishedin a number of different ways. In the principal illustrative embodiment of the invention the means for this purpose includes a four-motion feed dog andan auxiliary roller feed or puller mechanism. The latter may, if desired, be omitted. Moreover; the action of the feed dog may be supplemented by a needle feed movement of the needle bar,'wheneverdesired.

Referring now particularly to Figs. 1 to 6 inclusive, a feed dog I21 of appropriate form may be provided, the serrated or toothed portion of 1 the feed dog being arranged to extend upwardly through slots in the usual throat plate provided in the work supporting surface. The feed dog is carried by a feed bar I28 towhich it is adjustably secured by screws I29 and I30. Feed bar I28 is pivotally connected-at I3I with a feed rocker I32 secured to a shaft I33 suitablyjournalled in bearings provided in the base of the machine. In the portion of the base directlybelow the vertical standard II there is secured to the shaft I33 a yoke I34 of generally U-shaped configuration. This yoke is clampedto the shaft by means of a screw I35. One of the arms of the yoke carries at its outer end a laterally'extending pin [36 cooperating with a strap at the lower end of a'connecting rod I31 'whose upper end is "similarly connected with a'pin 138 carried by an arm I39 secured to a rock member l40. The pins I36 and I33 and the strap portions of the rod I31 are preferably provided with spherical cooperating surfaces. Member I40 in the construction illustrated is adapted to rock about the axis of shaft I3. It may, for this-purpose, be freelymounte'd upon an extension -of the"adjacent bearing for this shaft. If it is desired to provide the machine with a needle feed action; on the other hand, the member I40 will be secured to a sleeve-capable of transmitting the motion of the member to a frame in the needle head in-which the needle bar is slidably mounted. A suitable arrangement of this character is disclosed in the Christensen application, Serial No. 582,876, filed March 15, 1945.

A sleeve-like member I 4I- (Fig. 6) is provided with a lateral extension having astrap arranged to cooperate with an eccentric I42 secured to shaft I3. Slidable'within the sleeve MI is a rod I43 to which is secured a yoke or'collar I44 carrying a pin I45 providing a pivotal connection with a member I46 secured to a rod- I41. The latter is adjustably mounted for axial sliding movement in suitable bearings in the frame of themachine. Vertical adjustment of therod I41 may beeffected by turning the knurledheadf I48 of a member which hasla screw threadewstem that engages threads in and supports the rod I41. A lock nut I 49 cooperating with threads onthe member I48 serves to lock theparts in adjusted position. Below the collar I44 there is slidably mounted on the rod I43 a collar I50 which is pivotally connected at I5I with the lower end of the rock member I40. The foregoing arrangement is. such that as .the

shaft I3 is rotated the sleeve I4I"wi1l be shifted I l 10 will. in turn, be imparted through the collar I50 to the lower arm of the member I40. The extent of rocking of the member I40 may be varied by varying the position of the pivot I45 through adjustment of the knurled member I48. For further details as to the construction and operation of this mechanism reference may be had to said Christensen application, Serial No. 582,876.

Rocking of the member I40 in the manner explained will impart corresponding rocking movements to the yoke I34 and to the shaft I33 so that the feed rocker I32 will impart the feed and return movements to the feed dog I21. In synchronism therewith the feed dog will be lifted and lowered by means of an arm I52 connected at one end with the feed bar and at its opposite end pivotally connected with a strap member I54 cooperating with an eccentric I55 carried by the shaft I6.

' The other arm of the yoke I34 is provided with an elongated slot I56 along which a bolt I51 may beadjusted and then secured in any desired position. This bolt provides a pivotal connection witha link I58 attached at its upper end by a screw I59 to an arm I60 integral with a driving plate ISI of a one-way roller clutch of the type disclosed in the Long, et 21. Patent No. 1,692,130, granted November 20, 1928. A spool-like member I62 which encloses the rollers and other internal mechanism of the clutch is secured to a shaft I33 which is mounted in suitable bearings in the base of the frame and which extends into the region of the line of feed of the work. A plate I64 at the opposite end of the spool from the plate I6I has a bent-over extension I65 Which is secured by screws I66 to a part of the frame. This plate I64 carries the part of the clutch structure which prevents retrograde movement of the spool during the reverse or idle movements of the driving plate IBI. For further details as to the construction and operation of the clutch, reference may be had to said Long, et al. patent. To the forward end of the shaft I63 there is secured a feed roller I61 which may be suitably grooved, serrated, or knurled, if desired, to assist in feeding the work. I I I Suitable presser members are provided to cooperate with the feed dog I21 and the feed roller I51 in advancing the work. Referring to Fig. 3, a presser foot I68 carried by a presser bar I69 cooperates with the feed dog I21. The presser bar is mounted for vertical movement in suitable bearing sleeves in the needle head and is normally urged downwardly by a spring I10 00- operating at its upper end with the bottom of a screw threaded sleeve I1I which may be adjusted to vary the tension of the spring. At its lower end the spring engages a block I12 secured to the presser bar. Lifting of the presser bar to permit insertion and removal of the work is accomplished by a sleeve I13 slidably mounted on the presser bar and connected by a link I14 with an arm I15 carried by a rock shaft I 16. The latter is suitably journalled in the overhanging arm of the frame and at a point adjacent the vertical standard is provided with a rearwardly extending arm I11 (Fig. 6) which is connected by a rod. I18 with a suitable foot treadle for controlling the lifting of the bar. The linkage for this purpose may include a rocker member I18a rockably mounted on the rear side of the base of the machine beneath the work supporting surface.

For cooperation with the auxiliary feed or puller roller I61'there is provided a separate detachable frame member I19 adapted to be secured by screws or the like (not shown) to the needle head of the main frame. Suitably mounted in the auxiliary frame for vertical re ciprocation is a bar I80. A yoke I8If is secured to the lower end of this bar and supports a horizontally disposed shaft I82 which carries a presser roller I83 arranged to cooperate with the feed roller I61. For the purpose of yieldingly urging the presser roller I83 against the feed roller a spring I as is provided around the bar I88 and is arranged to cooperate with the lower end of a threaded sleeve I85 which may be turned to adjust the tension of the spring. The lower end of the spring acts against a lug I88 secured to the bar I 80. For thepurpose of lifting the presser roller I83 against the action of the spring, a lever I8! is provided, this having a camming portion adapted to engage an extension of the lug I88. A downwardly and forwardly extending hooked portion I8! of the lug I86 is arranged to engage beneath a projection I88 integral with the sleeve I13. This arrangement is such that upon the lifting of the bar I38 by operation of the lever IS! the presser bar I 59 will also be lifted.

In machines in which the auxiliary roller feed or puller mechanism is not desired, a somewhat different construction of the feed dog operating mechanism may be employed. Referring to Fig. '7, a shaft I89 corresponding with the shaft I33 of Figs. 3, 4, and 6, may be provided, this being at a somewhat higher point in the base of the machine than the shaft I33. It may be operated in substantially the same manner as the shaft I83 through the use of a somewhat shorter con- 7 necting rod than rod I31 but similar to the latter. In the region of the feed dog the shaft I88 has secured thereto a feed rocker I98 to which is pivotally connected, adjacent its upper end, a feed bar I9I which carries a feed dog I92. The latter is secured thereto and adjusted by means of screws I93 and I 94. A forwardly and downwardly extending arm I95 rigidly secured to the feed bar and pivotally connected at its free end to a strap I95 cooperating with an eccentric I97 carried by the shaft I6, serves to impart the lifting and lowering movements to the feed dog. Means are thus provided for imparting a fourmotion movement to the feed dog.

As previously indicated, the machine provided with either of the feed mechanisms above described may also have a needle feed action of the type disclosed in said prior Christensen application.

The machine may be equipped with any of the usual accessory devices provided in machines of i the general character to which the invention relates. For example, rotary thread take-up mechanism indicated generally at I98 in Fig. 2 may be provided. This may be driven by a shaft I99 which extends throughout the length of the over-- hanging arm and which is connected by gearing 280 with the main drive shaft I3. For further details asto a suitable form of construction of such a rotary takeup, reference may be had to the above mentioned Christensen application, Serial No. 582,876. Such a rotary take-up will ordinarily be provided only when vertical hook units are employed to produce a lockstitch ma chine. -A simple reciprocatory or oscillatory take-up of known construction, such as that shown in the application of Norman V. Christensen, Serial No. 513,336, filed December 8, 1943, may be advantageously employed in the double lockedstitch machine.

Reference may be had to said prior Christensen application for other details of the machine, such as the thread tensioning devices shown generally at 20I in Fig. 2.

While a primary embodiment of the invention, and various modifications, have been illustrated and described in considerable detail, it will be understood that various changes may be made in the construction and operation of the various parts of the machine without departing from the general principles and scope of the invention.

What I claim is:

1. In a sewing machine having a frame with a work support provided with a drive shaft, a self-contained loop-taking unit comprising a saddle detachable from said frame, a rotary shaft in said saddle, gearing interconnecting said shafts, a loop-taker mounted on said saddle for oscillation substantially about the axis of said shaft in said saddle, and connections from said I rotary shaft to said loop-taker for oscillating the same. I

2. In a sewing machine having a frame with a work support provided with a drive shaft, a selfcontained loop-taking unit comprising a saddle detachable from said frame, a rotary shaft in said saddle, means interconnecting said drive shaft with said rotary shaft for driving the latter, a loop-taker mounted for oscillation substantially about the axis of said rotary shaft, and connections from said rotary shaft to said loop taker for oscillating the same, said connections comprising a lever pivotally mounted on said saddle, a link connecting said lever with said loop taker, eccentric means. on said rotary shaft, and a pitman connecting said eccentric means with said lever.

'3. In a sewing machine having a frame, a loop taking unit comprising a saddle detachable from said frame, a rotary shaft in said saddle, a looptaker mounted for oscillation substantially about the axis of said shaft, connections from said shaft to said loop-taker for oscillating the same, and

connections between said shaft and said 100; taker for imparting bodily movements thereto.

4. In a sewing machine having a frame, a loop-. taking unit comprising a saddle detachable from said frame, a rotary shaft in said saddle, a looptaker mounted upon an eccentric portion of said shaft for oscillation substantially about the axis of said shaft, and connections from said shaft to said loop-taker for oscillating the same.

5. In a sewing machine having a frame, a selfcontained loop-taking unit comprising a saddle detachable from said frame, a rotary shaft in said saddle, a loop-taker mounted for oscillation substantially aboutthe axis of said shaft, connections from said shaft to said loop-taker for oscillating the. same,- said connections including eccentric means carried by and rotatable with said shaft, a lubricant reservoir in said saddle, and means operable upon rotation of said shaft for distributing lubricant from said reservoir to bearing surfaces of said eccentric means, said lubricant distributing means including a passage formed in said eccentric means and means within said shaft and operable to transmit lubricant from said reservoir to said passage.

6. In a sewing machine having a frame with a work support provided with a drive shaft, a

self-contained loop-taking unit comprising a said rotary shaft for oscillation thereon, a plurality of loopers carried by said carrier, and connections from said rotary shaft to said carrier for oscillating the same and said loopers.

'7. In a sewing machine having a frame, a selfcontained loop-taking unit comprising a saddle detachable from said frame, a rotary shaft in said saddle, a loop-taker mounted for oscillation substantially about the axis of said shaft, connections from said shaft to said loop-taker for oscillating the same, said connections including eccentric means carried by and rotatable with said shaft, a lubricant reservoir in said saddle, and means for distributing lubricant from said reservoir to bearing surfaces of said eccentric means, said lubricant distributing means comprising pump means associated with said shaft and rendered effective upon rotation of said shaft and a passage formed in said eccentric means and communicating with said pump means.

NORMAN V. CHRISTENSEN.

14 REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 281,296 Post July 17, 1883 351,594 Harlow et a1 Oct. 26, 1886 421,590 Littlejohn Feb. 18, 1890 809,660 Ammerman Jan. 9, 1906 1,090,151 Hohmann Mar. 17, 1914 1,684,004 Becker Sept. 11, 1928 2,095,450 Myers Oct. 12, 1937 2,404,318 Sauer July 16, 1946 2,409,242 Becker Oct. 15, 1946' 

